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Dinosaur Hunt: Project Exploration's 2003
Expedition to Niger
Bone fever! Fossil
hunters hit pay dirt
By Paul C. Sereno
Special to
the Tribune
Published November 21,
2003
SOUTHERN SAHARA, Niger -- It has
been three years since University of Chicago paleontologist Paul
Sereno brought a team to Niger to explore the rich fossil beds
hidden by desert sands. This is the second of five dispatches from
the dinosaur hunt. In this installment, we get a snapshot of life in
the field . . . and a first taste of the discoveries the team is
making.
The 2003 Expedition isn't just on a mission to find
dinosaurs — we're trying to paint a detailed picture of what life
was like in Africa 90 million years ago. The discovery of a new,
strange crocodile at our second campsite triggered our first round
of "bone fever."
Josh Miller, a University of
Chicago grad student, suddenly thrust his hand to the sky, with a
wail. "Wow, look at this!" There, perched between his fingers, was a
monstrous croc tooth he had just plucked from the desert floor. We
all gathered to marvel at the finding of a new species. No croc of
this size — easily twice that of a large living croc — had ever been
found in 90-million-year-old rocks in Africa.
It wouldn't be
long before more of the mystery croc surfaced.
A few days
later, and 200 miles south of Josh's find, we were brought to
another stunning sight. "Jaws, incredible jaws," stammered Jeff
Stivers, a soft-spoken anthropology student from Colorado College.
He pointed. There, along the tips of his toes, was a row of teeth,
each nearly an inch in diameter, protruding from jaws diving into
the desert floor.
"This is great! More of mystery croc! You
got the front end!" I congratulated him.
We huddled around
the find on our hands and knees and began to compare the new,
curious croc with the well-known Sarcosuchus (a.k.a. SuperCroc).
SuperCroc is a 40-foot-long, dinosaur-eating crocodile that haunted
the waterways of Africa 110 million years ago — 20 million years
earlier than the fossils now being unearthed by the team. What was
this new croc? Could it be a smaller relative of Sarcosuchus, a
lineage that had gone extinct? Or is it possibly even more closely
related to living crocs?
As the crew followed the jaws into
the rock with brushes, small picks and dental tools, more of the
skull emerged. The work continued well into the afternoon: Bony
armor plates from the back surfaced, as did tail vertebrae. We
assessed our water, plaster and burlap. We had just enough to encase
the discovery in a "jacket" and bring it back to camp.
After
hours of work under intense desert sun and temperatures that reached
120 degrees, the jacket encasing the skull was complete. Weighing in
at about 300 pounds, the team lifted and shoved it into the back of
a Land Rover.
This team isn't only motivated by extinct
reptiles. For one of us, in particular, living reptiles are worth
getting excited over too.
A recent University of Chicago
graduate and a research assistant in the Field Museum's herpetology
department, Luke Mahler seems to have a natural attraction for
reptiles. One afternoon, as we were driving to our next prospecting
area, Luke sighted a familiar shape. "A monitor!" he shouted into
the radio.
Taking measurements
The vehicles
made a hurried stop. Alarmed by the rumble of the approaching
expedition convoy, a beautiful lizard vaulted its 2-foot-long, scaly
body down a burrow under a long-abandoned truck tire. With gloved
hand, Luke pulled the tan lizard from its hideaway for measurements
before releasing it to scurry back down its hole.
That night,
as dark was falling, Luke pulled a chair a short distance from camp
to write in his journal. Minutes later, he found a venomous snake
coiled between the legs of the chair, inches from his feet. Thrilled
by his late-night visitor, he bagged the beast, and proudly showed
the team the next morning before he released it — a good distance
from camp.
Reptiles are one thing; the desert's living
invertebrates — insects, scorpions and arachnids known as wind
scorpions — tend to generate more stress than excitement. This year
was a wet one by Saharan standards, with some areas receiving as
much as 2 inches of rain, and the water has gotten the desert
crawling. As a result, we have taken to choosing our campsites
carefully. "Almost no bugs here," I proclaimed with confidence, as
the crew set about erecting the big tents at Camp Two.
But by
the following evening, what had been a bug-free zone transformed:
Hundreds of locusts began dive-bombing the camp, attracted by the
water, vivid colors and night lights. Each evening, the party grew.
By week's end, thousands of locusts had invaded our desert
home.
Even Carol Gudanowski, a recent University of Chicago
graduate and one expedition member not particularly fond of
six-legged creepy crawlers, couldn't help but be drawn in when the
team spotted an illustration of the food chain in action. She was
shivering — but fascinated — as she joined the group watching a
locust being eaten by a preying mantis, which, in the same moment,
was being eaten by a wind scorpion.
When members of the team
aren't pitting wind scorpions gladiator-style against dung beetles
in arenas made of coffee cans, or scooping up cold-blooded reptiles
for measurement, we can sometimes be found collecting recent
skeletons for a comparative study collection — our best addition to
date is a dinosaur descendant Luke found after a long day of fossil
prospecting.
"Complete bird, we got to check it out,"
announced eagle-eyed Luke, who had spotted the feathered carcass
against yellowed grass on our way back to camp one afternoon. I
swung the Land Rover around. Sure enough, a large vulture lay there,
untouched by scavengers, but swarmed by hundreds of dermestid
beetles, which were fast reducing its remains to a skeleton,
virtually intact.
Luke and Andy Gray bagged the reeking
remains, and as they tied it to the roof rack, we could hear the
beetles scratching around in the bag.
We are, however, on a
paleontology expedition, and this is our primary obsession.
I
caught my breath when I spotted a 3-inch-long neck vertebra on the
side of a hill. Walking carefully along the trail of fragments, I
spotted the rest of the neck diving into the red rock. Other slender
bones projected from the hillside.
"I think it's a small
theropod!" I yelled out and called French paleontologist Ronan
Allain over to the site. Ronan, who had just finished his doctorate
on predatory dinosaurs from France, was wide-eyed as he began to
pore over the bones beside me.
"They're hollow, and the neck
is clearly inclined upward" he noted. Other team members arrived and
helped brush back the sediment and gather wayward pieces. Each of us
knew what the others were thinking: Could this possibly be a
raptor?
Velociraptor and Compsognathus of "Jurassic Park"
fame belong to a group of small predatory dinosaurs often referred
to as "raptors." For dinosaur aficionados, the list of precious
raptors is long and includes the sickle-toed Deinonychus and the
fleet-footed Troodon from Montana. Recently named raptors include
the feathered Sinornithosaurus and Microraptor from
China.
Northern climes inhabitants
To date,
raptors share one common characteristic — they all come from
northern continents. The fossil evidence for raptor-size dinosaurs
is terribly lopsided. There is almost no information available from
southern landmasses such as Africa.
As we continued to work
to figure out how much of the "raptor" skeleton was preserved, we
came across the tail of another, larger, predatory dinosaur less
than a foot away. The bones of the smaller "raptor" were so delicate
that we dared not expose them further in the field for fear of
damaging them. We dug around our new, little southern "raptor," and
took all the bones in a single jacket. Doubtless a new species, the
small predator will remain an exciting enigma until the jacket is
opened and cleaned in the lab back at the University of
Chicago.
With new crocs, and two new predators jacketed we
are just halfway into the field season — and the outlines of the
story of what life was like in Africa at the end of the dinosaur era
are starting to take shape.
Project Exploration is a
non-profit science education organization co-founded by
paleontologist Paul Sereno and his wife, educator Gabrielle Lyon, to
make science accessible to the public — especially city kids and
girls. For more stories and photos from the 2003 Niger Expedition,
log on to www.chicagotribune.com/dino and
www.projectexploration.org.
Copyright © 2003, Chicago Tribune
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